Mold for making dental plates.



J. W. GREENE.

mom) FOR MAKING DENTAL PLATES.

APPLICATION FILED JAN. 18, 1913.

Patented 1m 4 19-13;

B sn'nm'a-annr 1.

WITNESSES Whiz/L J. W. GREENE.

MOLD FOR MAKING DENTAL PLATES.

APPLICATION FILED .TAN.18, 1913.

1,077,703,! Patented Nov. 4, 1913.

2 SHEETS-SHEET 2.

, 2602 y feefleiv W 4 M I INVEZ/VTOR aha/M A;

WYTAESSES TD sna s PATENT enrich.

JACOB W. GREENE, 01' CHILLICOTH-E, MISSO'IJRII.

MOLD FOR MAKING DENTAL PLATES.

I Specification or ltetters Patent.

Application flledianuary 1 8, 1913. Serial No. 742,962.

dental plates designed more particularly to strengthen the investment inthe construction of artificial dentures.

In the usual method of setting teeth on a plate, especially ofvulcanized rubber plates, an investment of a fresh mixed plastercompound is poured into a mold and put under pressure in the ordinarymanner. The plaster of Paris, or compound, has been found defective forthis pur ose, in that it disintegrates under heat an moisture, andyields under the pressure requiredin roducing vulcanized dental plates.his frailty or uncertainty in the employment of such materials resultsin orosity and miss fitting dental plates, and in malocclusion inartificial dentures. Moreover, it frequently happens that in pouring andfinally filling the last half of a dental flask or mold and in order toreach narrow and somewhat inaccessible places, the plaster investmentmust be too thinly mixed to produce a strong body, hence the investmentso formed is correspondingly weak. This is especially true when airbubbles occur in the pouring.

covered the model.

Furthermore, dentists often find their rubber plates comelout of thevulcanizer much thicker than the. base plate pattern which This extrathickness maybe attributedto the compressive yieldplaster investmentwhere ing of the fault he roof arch of the model it antagonized t g orcast.

To remedy the defects specified, I employ supporting devices for theinvestment, one of which devicesoperates to retain the teeth in theirocclusive position and the other device serves to prevent the dentalplate from assuming extra thicknessduring the molding and vulcanizingprocesses, both of which devices operate to strengthen the investment.

The invention consists in the employment of an adjustable element whichmay be readily positioned oVer,-or onto,

teeth after they have been set and arranged on the usual base plate intoocelusive'position, said element comprising a substantially curvedstructure having a front Wall and a rear wall, producing a channelbetween said Walls for the reception of the teeth, and means forsecuring the device in position.

The invention consists, further, in the process, and the employment of apalatal Patented Nov. 4, 1913. g

support wherein a layer of investment may vention, but the constructionsshown therein are to be understood as illustrative only and not asdefining the limits of the invention.

Figure 1 is a transverse sectional view through a dental fiask or moldshowing the employment of the devices. Fig. 2 is a plan view of thetooth and palatal supports 1n position on a plate. Fig. 3 1s aperspective view of the palatal support. Fig. 4 is a perspective view ofthe tooth-supporting element. Fig. 5 is a sectional view on the line 55of Fig. 4. Fig. 6 is a plan view of another embodiment of thetooth-supporting element, andFig. 7 1s a sectio'na new on the line 77 ofFig. 6. Fig. 8 1s a fragmentarv view of another embodiment of theinvention. v

The invention contemplates the use of an ordinary dental flask havingthe upper section 10 and the lower section 11, which is adapted tocontain the usual investment material indicated at 12, which may beplaced in the flask in the ordinary manner.

After the model' of the month has been i made and the other preliminarysteps taken, the artificial teeth are set in their occlusive positionand are retained in said position byxa tooth-sugporting element 1?), 1nthe form ofa rein orcing plate. TlllS element is disclosed in Figs. 4and 5 show ing the same provided with a vertical wall the arch 01114 anda substantially horizontal wall 15 forming a channelbetween said wallsfor the reception of the teeth. In Fig. 5, the reinforcing plate 13 isbent so that the walls form an angular channel. This plate may be madeof anysuitable material, and in Figs. 4: and 5, this element is shownprovided with plain walls. This tooth supporting element is adapted tobe bent in proper shape to lit the contour or arch shape of theartificial teeth which have been set in wax, the outer edges of theteeth fitting Within the V-shaped channel of the tooth-supportinelement. At the ends of this element, t e walls are separated or split,as at 16, to permit the lower wall 15 to be bent outwardly, forming ananchor 17 for the tooth support to enga e the surrounding investment,while the ree end of wall 14 is bent, as at 18, to produce a clip orclamping means for retaining the support upon the teeth.

Prior to applying the support to the arch of teeth, it is preferred toplace some of the investment in the V-sha channel, and to allow theteeth to rest 1n this investment.

and be sealed in position thereby. In this construction of the device,it may be stamped or otherwise produced as a whole and still haveadjustable mobility to fit in place on the teeth, as will be readilunderstood. In 6 and 7, however, have illustrated a modified form of thetoothsupporting element in which the lower wall 15 is provided with anumber of transverse slots 19, and also with a plurality of aper tures20. As the slitting of this lower member 15 may weaken the plate, ifmade of very thin metal, it may be found desirable to reinforce theplate by doubling either or both of the walls upon themselves, moreparticularly the front wall 14, as shown at 21 in Fig.. 7. The the slots19 permits the easy a justment of the tooth-su porting element to an arcof teeth as it a] owe the bending of the element to take place aroundthe wall 14 or 14-21 thereof. The provision of the a rture' 20 permitsthe investment to prot-ru e through said apertures and thereby lock theplate more firmly in position on the teeth. If desired, the surplusmetal may serve as anchoring means, as shown in Fig. 7. Shoul'd thinmetal be used, it may be desirable to crimp or corrugate thewalls 14, or15, as

shown in Fig. 8 By the em loyment of this tooth-supporting element,tiliet'eeth are always maintained in their occlusive osition and areprevented from a reading apart during the molding and vu'l caniaingprocesses. This is esially true where gum-section teeth are used and thejoints are apt to open bythe yielding oi unsupported, faulty las erinvestment.

(loiipers. a tGQtll-$ilF o eiement 3.3, anti-or. pi? e5 rovision of whatI c aim as new and desire to secure dental plates is a palatal support22 which is designed to prevent the collapsing or distortion of the roofor vault investment. In Fig. 3, the palatal support is shown as a. thinplate having depressions and curved 70 surfaces to substantially conformto the roof of a base plate. This palatal or reinforcing plate may beconstructed of any desired material, such as cast metal, sheet metal,and is adapted to be placed in position prior to the application of theplaster investment around the model. A thin layer of plaster investment23 is placed upon one surface of the palatal plate 22, and the plate isthence set in pos tion neat to the roof of the model, or base plate. Asshown in Fi 2, the tooth and palatal supports 13 and 2 respectively,-operate, toget-her with the plaster investment and model in connectionwith them, to maintain the teeth and" the model plate in their properpositions. The application of this palatal plate also prevents thevulcanized plate from assuming a distorted surface or becoming too thickduring the molding or vulcanizing process by preventin compression inthe plaster investment. t may be found desirable, also, to provide theplate 22 with a series of apertures 24, serving as anchoring means forthe plate, said apertures permitting the investment to pass throu h thesame and thereby secure the platein its adjusted position on the model.This roof support, or palatal plate, prevents the yielding of theplaster investment under it during the process of packing andvulcanizing. The plaster investment is placed in the lower half of themold 11 in the usual manner, and the model with the palatal and toothsupport therein, as described," is next placed in position in the flask.After the palatal support has been placed firmly in position, theinvestment 1s then poured around the rest of the model, in the usualmanner, for the vulcamzing molding process.

Havin thus fully described my invent1on,

Letters vPatent is 1. In a device of the character described, thecombination, with a dental flask, a dentel model, and the investment ofthe flask, of

' a tooth-supporting element adapted to be positioned over the teeth,and means for retaining said tooth supporting element in po- 120 sitionfor the purposes described.

' 2. In a. devioeof the character described,

the combination, with a. dental desk, a, den- 7 tel model, and theinvestment of the dash,

of a tooth supporting elent adapted to be 12% positioned over the archoi the teeth, said topth support-in element com. u-

o .ysr p o the combination, with a dental flask, a den- .tal model, andthe investment of the flask; of

a tooth-supporting element adapted to be positioned over the teeth, saidelement being provided with a channel for the reception of the teeth, athin layer of investment within said channel and substantiallysurroundin the teeth, and means for securing the toot I supportingelement in position. 4. In a device of the character described,

rtlie combination, with a dental flask, a dental model, and theinvestment of the flask, of a palatal support positioned over the archor ,roof of the base plate, and means for separating the alatal supportfrom the dental mold, for t e purpose described.

5. In a device of the character described,

7 the combination, with a dental flask, a dental model, and theinvestment of the flask, of

a palatal support positioned over the arch or roof of the base plate,and a thin layer of investment positioned between the support and thebase plate.

a substantially pliable plate having a plurality of walls forming achannel, means on said plate for securing the same to the teeth, andmeans for anchoring the plate within the investment of a dental mold orflask.

8. A tooth-supporting element comprising a plate having a pluralit ofwalls forming a channel, one of said wa ls having a plurality of slotsand a plurality of perforations, means at each end of the plate forsecuring the same to the teeth of a dental model, and means at the endof the plate for anchoring the same in the investment of a dental model9. In a; palatal support of the character described, a plate having anirregular surface of substantiall the contour of the human mouth, said pate being provided with a plurality of perforations.

10. In a palatal support of the characterdescribed, a plate having anirregular surface of substantially the contour of the vault of a humanmonth, said plate being provided with a lurality of perforations and amu hene surface, for the purpose descri d.

In testimon whereof I aflix my signature,-

in presence 0 two witnesses. JACOB W. GREENE.

Witnesses:

R. W. REYNOLDS, L. N. Pnnm.

